Archives of Nethys

Pathfinder 1E | Pathfinder 2E | Starfinder

Armor | Shields | Weapons
Artifacts | Augmentations | Creature Companions | Computers | Hybrid Items | Magic Items | Technological Items | Traps
Manufacturers | Other Items | Special Materials

Advanced Melee | Ammunition | Basic Melee | Grenade | Heavy | Longarms | Small Arms | Sniper | Solarian | Special
Critical Hit Effects | Special Properties | Weapon Accessories | Weapon Fusions

Weapon Fusions

A weapon fusion is a small, prepackaged add-on that can be attached to any weapon to infuse it with magic. Adventurers use weapon fusions to customize their weapons for a specific enemy or to increase a weapon’s overall effectiveness. Weapon fusions are magic unless stated otherwise. While this causes the weapons they are installed in to be considered hybrid items, in truth the weapon and the fusion still operate separately. An ability that affects a magic item could affect the fusion installed in a weapon, but that would not prevent the weapon’s core function from operating normally unless the weapon was also independently a magic device. The hybridized fusion (see page 194) is an exception to this rule, as noted in its description. Weapons with fusions are considered magic for the purpose of overcoming damage reduction.
Click here for the remaining rules on Weapon Fusions.


Source Starfinder Core Rulebook pg. 195
Item Level 2
A weapon with the spellthrower fusion is able to have a single spell gem loaded into it at a time. It takes 1 minute to load a spell gem, and only gems containing a spell with a casting time of one standard action or less and a spell level no greater than one-quarter the weapon’s item level can be loaded into the weapon.

If you are proficient with and wielding the weapon, as a full action you can cast the spell contained within the spell gem rather than make a normal attack. This allows you to use the spell gem as if you were a spellcaster with the spell on your class’s spell list.

Unlike the normal rules for using a spell gem, it does not matter if the gem’s item level is higher than your caster level (even if your caster level is 0). However, if the spell gem’s item level is higher than your base attack bonus, once you’ve spent the full action to cast the spell, you must succeed at an attack roll with the weapon against an AC equal to the spell gem’s level + 1 or you fail to cast the spell. This roll represents your expertise with the weapon, and no actual attack or ammunition is used. If you fail to cast a spell from a spell gem, the spell is expended harmlessly and the spell gem is destroyed.